We've been hard at work on our ultibots and have come up with a couple of bots.

FLAME BOT (unnamed)

Sentry bot with flamethrower for hiding the tennisball behind.
The plan is to have this working with a car fuel injection pump pushing kero. At this stage it isn't looking like this will be ready on time. Work sucks!!!


All terain bot (unnamed)

We've built a prototype all terain tracked robot. It takes insperation from Team Vertex's tracked bot.
At this stage it's weapon will be a water cannon, it has terible trouble turning and the tracks slip when we try. anyways we'll see how it goes on the weekend. We'll try to get photo's up before end of week.

Last edited by NMO on Sat Sep 16, 2006 7:00 pm; edited 1 time in total

MORE PICAXE STUFF

Mat and I have been working for the last couple of weeks on a picaxe relay controller that is simpler than the PRC. It only uses 3 relays instead of 8 but does loose 1 item of functionality, also at this stage it does not have any weapons control.

Here is a circuit diagram of it
http://www.robowars.org/forum/album_pic.php?pic_id=1304

The one thing it can't do that the PRC can do is have one motor running forwards while the other runs backwards. however Vincent did have issues of control under these conditions anyway.

We have 2 issues to solve before it will be battle ready.

-1- The direction control realy welded itself after about 2 mins today. 30A DPDT relay with 2 100W scooter motors on it. I think using 2 of the 60A horn relays will fix this

-2- Some radio glitching, we have already placed caps in various parts of the circuit with some success.

The problem with welding the relays is because of the 24v, not because of amperage. Andrew can tell you how he fixed teh same problem in Sproing with just a capacitor wired onto it
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https://www.halfdonethings.com/

Maybe, it is a 24volt 30amp relay.

I just realised there's a problem in my schmatic with the way the motors are wired to the relays. the basic idea still works but this is the issue when you draw the scematic after you build the design

ok welded relay problem seams to have been fixed. and since I used many capacitors to fix it some of the radio glitches seam to have stopped as well.

The next step will be to play with the code a bit to improve things.

Here is a photo of the controller. it's working pritty well at the moment, with no real issues

http://robowars.org/forum/album_pic.php?pic_id=1305

Here is the code

'2 channel robot onoff controller mixed
'by Team NMO
'19-9-2006

'THIS IS AN EXPERIMENTAL CONTROLLER USE AT YOUR OWN RISK


main:
pulsin 4,1,w0 'fb
pulsin 3,1,w1 'lr
if w0 < 90 or w0 > 210 or w1 < 90 or w1 > 210 then failsafe
if w0 > 175 then forwards
if w0 > 125 and w0 < 175 then neutral
if w0 < 125 then reverses
goto main

failsafe:
low 1
low 2
goto main

neutral:
low 1
low 2
goto main


forwards:
low 0
if w1 > 175 then fl
if w1 < 125 then fr
if w1 > 125 and w1 < 175 then fff
goto main

reverses:
high 0
if w1 > 175 then rl
if w1 < 125 then rr
if w1 > 125 and w1 < 175 then rrr
goto main



fl:
high 1
low 2
goto main

fr:
low 1
high 2
goto main

fff:
high 1
high 2
goto main

rl:
high 1
low 2
goto main

rr:
low 1
high 2
goto main

rrr:
high 1
high 2
goto main

high current wirering of controller

http://robowars.org/forum/album_pic.php?pic_id=1306

Mmmm... I have a few questions.

1. I noticed you have no provision in your code to prevent hysteris (sp?). Hysteris plagued my first controllers and after going back through some old code Ajax showed me, I was able to fix that problem easily. I created 5ms hysteris bands to prevent it.

I used the following definitions:

code:

---

;-RC Channel Definitions
symbol fail_low = 100 ;1ms - failsafe below here
symbol low_on = 135 ;low activate point
symbol low_off = 140 ;low deactivate point
symbol neutral = 150 ;where motor is off
symbol high_on = 160 ;high deactivate point
symbol high_off = 165 ;high activate point
symbol fail_high = 200 ;2ms - failsafe above here

---

Some good points there Aaron,

-1- I haven't used histerisis at this stage purly to keep things simple, but you are right that it could improve things. Also I hadn't thought of it.

-2- <= well I new I had forgotten something, but I'll incorperate that into the next version of software.

-3- Yep 08M chips. I'm trying to build the cheapest controlers I can and the 18x would increase the costs by $16.80 using the pcb's from Microzed (I hate vero board with a passion so use it as little as possible.)

Thank's for the feedback. Much appreciated. Many minds make light work.

The cost so far is around $80 and half of that is relays.

lol. I have designed all my designs to run on 08M's simply because I'm too cheap skate to buy the 18X programmer

Veroboard is a pain in the ass, but it does leave a lot of flexibility
_________________
https://www.halfdonethings.com/

For Prototypes, I like "Donut Board" (The one with seperate holes instead of strips) from Jaycar better than Vero. I use single strand teflon wire-wrap wire (Kynar) to do point-to-point wiring rather than cutting Vero tracks all over the place.

The only catch is you need to find a wire-wrap-wire stripper. The look like a little v-notched razor blade. they can be difficult to locate, but once you have one, point-to-point is much easier than vero drilling
_________________
Great minds discuss ideas. Average minds discuss events. Small minds discuss people

I just use the long tail ends off the components lol

I work best similar to spocky using the jaycar donut boards,
but I tend to use telephone / cat5 cable wires instead of
the teflon stuff.

That way I can still have multiple colors to choose from and
from a really cheap source. (dumpster diving )

After all, who doesnt have tonnes of telephone cabling or
dead network cables lying around being used as rope?
( or am I weirder than I thought? )

Also, what 18X programmer are you talking about? What
development tools (software) are you using? I'll edit them in
when I get home, but I use the same set of FREE (legit)
software tools, and a home-built programming cable to
do all versions of the 08 and 18 picaxes.
_________________
"The future is not set. There is no fate but what WE make."
........CEO Cyberdyne Systems